月: 2024年1月

What Is a Monofin?

A Monofin is fin-shaped like a dolphin’s tail. Unlike conventional fins worn on each foot, a Monofin requires both feet to be placed inside.

Monofins are used for swimming with a dolphin kick, similar to the butterfly stroke. The swimming technique differs from the individual fin strokes for each foot, placing a strain on the hips as the body undulates like a dolphin. With practice, swimmers can perform jumps from the water surface and even swim upright with the upper body above the water. Monofin swimmers can achieve speeds 1.5 times faster than advanced freestyle swimmers. Next-generation Monofins feature joints and mechanisms for adjusting propulsion, creating movements closer to a dolphin’s tail. The fins are also downsized, enabling faster kicks, and advanced users can swim at twice the speed of competitive swimmers.

How to Use a Monofin

The use of Monofins allows for enjoyable activities such as swiftly swimming in the sea like a dolphin and performing acrobatic jumps from the water’s surface.

There are speed swimming competitions known as fin swimming, where participants wear fins. Various underwater sports include surface snorkeling, immersion competitions using small scuba tanks, and breath-hold diving competitions (Apnea). While considered a minor sport in Japan, it is an official discipline in the World Games, often referred to as the Second Olympics, and is widely popular globally. Free diving competitions, where participants compete to dive as deeply as possible without equipment, are also held.

There are costumes resembling mermaid tails that go up to the waist, allowing individuals to become mermaids and enjoy taking picturesque photos. Swimming in the sea may also attract the interest of dolphins, prompting them to approach.

What Is a Pedal Kayak?

A Pedal Kayak, also known as a foot-pedal kayak, is a type of kayak propelled by pedaling with the feet, moving a propulsion mechanism attached underneath the kayak to navigate rivers and seas.

There are two main types: Mirage Type and Propeller Type.

The Mirage Type features a fin called the Mirage Drive developed by Hobie on the kayak’s hull. It excels in propulsion force, allowing easy-forward movement with light pedal strokes. This type is recommended for long-distance travel or individuals lacking confidence in physical strength. However, it cannot move backward and has limited maneuverability. The Mirage Type is also relatively expensive, with prices exceeding 300,000 yen.

The Propeller Type involves a kayak with a screw attached to the hull. It offers better maneuverability, including the ability to move backward. However, compared to the Mirage Type, it has slightly less propulsion force and can be more taxing on the legs and lower back. While not ideal for long distances, it is recommended for navigating in tight spaces. Prices for the Propeller Type start from around 200,000 yen.

Uses of Pedal Kayaks

Pedal kayaks find application in fishing.

Kayak fishing, the method of using a kayak to move along rivers, coasts, lakes, etc., for fishing, is gaining popularity. This approach, known as kayak fishing, involves using the kayak specifically for fishing rather than using it intermittently between boat travels.

Kayak fishing, being a convenient and active pursuit, has become popular in the outdoor community. With pedal kayaks that can cover long distances, anglers can easily navigate to the middle of a lake or venture out to their favorite fishing spots in the sea.

The advantage of pedal kayaks lies in their smooth and silent movement, allowing anglers to approach fishing points without alerting the fish. Additionally, it is possible to enjoy fishing with a beloved pet by bringing them along on the kayak.

What Is a Base Layer?

A Base Layer refers to outdoor underwear worn directly against the skin.

Also known as the First Layer, it is the first layer of clothing worn and is designed to quickly absorb sweat, separate moisture from the body, and expel humidity. Its quick-drying nature helps prevent chilling, and by keeping the skin dry, it aids in maintaining body temperature.

The predominant materials for Base Layers are synthetic fibers, although natural Merino wool, a type of wool with antimicrobial properties that resist odor, is also utilized. Merino wool is resistant to bacterial growth, keeping unpleasant odors at bay, and offers added moisture retention benefits when used in winter. When searching for Base Layers, options are often more abundant in mountaineering-oriented products rather than marine-specific ones.

Uses of Base Layer

Base Layers are particularly useful in marine outdoor activities such as diving and sea kayaking. In diving, where wetsuits are worn, avoiding cooling due to sweat is essential.

Products made from natural materials like cotton or rayon, with high water absorption and retention properties, should be avoided. Instead, products made from synthetic fibers such as polyester, which dry quickly, are more suitable. For frequent divers, Base Layers specifically designed for diving, such as those for scuba diving, are preferable.

During winter sea kayaking, layering with Base Layer, mid-layer, and outerwear (shell layer) is crucial for warmth. Base Layers made from natural Merino wool are well-suited for this purpose.

Because it doesn’t rob body heat even when wet, the buttocks don’t feel excessively cold. When engaging in outdoor activities during winter, Base Layers are indispensable.

Principles of Base Layer

The materials for Base Layers are primarily classified into three categories: synthetic fibers, wool, and hybrid, a blend of synthetic fibers and wool.

1. Synthetic Fibers

Excellent in moisture-wicking and quick-drying properties, synthetic fibers are resistant to abrasion. However, they can feel cold when wet with sweat, and unpleasant odors may develop after prolonged use.

2. Wool

Wool has a natural deodorizing effect, making it resistant to unpleasant odors. It doesn’t feel as cold when wet with sweat and provides high insulation. However, it has inferior abrasion resistance and drying speed compared to synthetic fibers.

3. Hybrid

Hybrid materials combine the characteristics of synthetic fibers and wool. However, compared to 100% synthetic or 100% wool, they may have inferior properties such as abrasion resistance, moisture-wicking, and deodorizing effects. Synthetic fibers are suitable for heavy sweating, while wool is preferable for those sensitive to the cold.

Structure of Base Layer

The neck structure of Base Layers comes in two types: zip neck and round neck. The fabric thickness of underwear can be selected, with options like lightweight and mid-weight.

1. Zip Neck

The zip neck prevents sunburn around the neck and allows temperature regulation by opening and closing the zipper. Its technical appearance makes it unsuitable for town use.

2. Round Neck

Round neck is common in casual wear and doesn’t look out of place in urban settings. It lacks temperature regulation capability, and a large area around the neck is exposed to UV rays.

3. Lightweight

Lightweight fabrics are thin and dry quickly when wet with sweat. They remain cool during activities and have excellent quick-drying properties. However, they offer lower insulation, making them suitable for summer.

4. Mid-Weight

Mid-weight fabrics are thicker, providing moderate insulation. Intense physical activity in summer may cause overheating, making them more suitable for spring or fall.

Types of Base Layer

The silhouette of a Base Layer can be categorized into underwear and shirts. In comparison to snug-fitting underwear, shirts are more relaxed.

1. Underwear

Conforming closely to the skin, underwear quickly absorbs sweat. However, it may not be suitable for standalone activities when worn alone.

2. Shirts

Concealing the body’s lines, shirts are easy to wear as a single layer. Due to the fabric being away from the skin, they have lower water absorption compared to underwear.

What Is a Kneeboard?

A Kneeboard refers to a type of board shorter than a surfboard, ridden in a kneeling position rather than standing, similar to sitting on one’s knees. It is also the term used for water sports involving the use of such a board.

Originating in Sydney, Australia, during the 1960s, when longboards were predominant, Kneeboarding emerged as a pursuit of greater speed and carving thrills (riding waves while carving them).

The dimensions of the board typically range from approximately 49 to 60 inches in length and 20 to 24 inches in width. The prevalent type features two fins on the bottom, resembling the dorsal fins of a fish.

To ride the waves, the rider attaches fins to their feet, kneels on the board, and controls it through weight shifts.

Enthusiasts of Kneeboarding are often referred to as “Kneeboarders” or simply “Knees.” The popularity of Kneeboarding significantly declined in the 1990s with the rise of bodyboarding.

Uses of Kneeboard

Kneeboards find application in marine sports such as surfing in the ocean, as well as engaging in recreational activities on lakes and rivers, often towed behind water skis or boats.

In contrast to standing on a surfboard, riding a Kneeboard in a kneeling position offers a closer proximity to the water’s surface. This perspective makes even small waves appear larger, providing a heightened sense of speed. The lighter weight of Kneeboards compared to traditional surfboards allows for easy turns with minimal weight shifts. Moreover, the proximity to the water surface allows riders to interact with the waves more closely.

Kneeboarding contests are held annually in Victoria, Australia, showcasing the sport’s popularity. Due to the ability to ride in a kneeling position, Kneeboarding is accessible to individuals with disabilities, and Para Surfing events are organized. Kneeboarding behind motorboats has become a popular summer leisure activity, enjoyed by women and children alike.

What Is a Dry Suit?

A dry suit is a type of attire worn when submerging underwater, such as in the sea or lakes.

Designed with waterproof features to prevent water infiltration into the suit, it serves various purposes. It not only protects against life-threatening conditions in cold underwater environments but is also suitable for tasks in water containing contaminants. Additionally, it prevents a drop in body temperature and comes in various types, including suits with excellent insulation properties and those combined with innerwear.

Dry suits are categorized into two types: the neoprene type, made from synthetic rubber, and the shell type, constructed with waterproof materials like nylon. In Japan, dry suits made of synthetic rubber are commonly used.

Uses of Dry Suit

Apart from preventing water infiltration, dry suits provide insulation to protect body temperature. These dual functions make them suitable for activities in low water and air temperatures, both underwater and on the water’s surface.

For underwater activities, dry suits are worn when the water temperature is approximately below 23°C. They are used in leisure diving, underwater construction work, search and rescue operations during water emergencies, and fishing conducted through diving.

On the water’s surface, they are utilized primarily during colder seasons for marine sports such as surfing, windsurfing, jet skiing, and yacht sailing. In situations where individuals involved in rescue operations or fishing are at risk of falling into cold water, dry suits are worn for protection.

Principles of Dry Suit

Dry suits are one-piece garments, including integrated boots, gloves, and hoods. The loose fit allows for the wearing of dedicated innerwear between the suit and the body. They are donned and doffed through waterproof zipper openings, effectively preventing water penetration, and maintaining a protective seal.

Structure of Dry Suit

The materials used in dry suits vary between neoprene suits and shell suits.

1. Neoprene Suits

Neoprene suits use foamed chloroprene fabric, often with jersey or fleece on the inside and jersey on the outside. The outer surface of the foamed chloroprene rubber fabric is radially coated with a rubber-like non-absorbent material.

2. Shell Suits

Materials used in shell suits include compressed neoprene, biaxial laminate, triaxial laminate, vulcanized rubber, and waterproof breathable fabrics. Compressed neoprene fabric with high hardness is used. Biaxial and triaxial laminates involve attaching fibrous fabric to one side of a waterproof film, while vulcanized rubber refers to materials where polyester fabric is coated with elastomer. Waterproof breathable fabrics such as Gore-Tex are also used.

Types of Dry Suits

Dry suits are mainly classified into neoprene suits and shell suits.

1. Neoprene Suits

Most dry suits available in Japan are neoprene suits. Constructed with foamed chloroprene fabric, they have a tight fit and provide insulation even if water enters the interior. However, they are not suitable for use in cold water without thick undergarments, and their insulation cannot be adjusted, making them less suitable for warm water.

Foamed neoprene fabric, containing air bubbles, changes insulation properties with surrounding water pressure and is prone to pinhole formation. While excelling in underwater mobility, they have limited mobility on land.

2. Shell Suits

Shell suits are made with waterproof fabric, offering a loose fit. They lack inherent insulation, relying on innerwear for thermal protection, making them suitable for extreme cold to high water temperature environments. While underwater mobility is limited, they provide excellent mobility on land due to the lack of necessary fabric stretch. They are durable and offer strength without changes in buoyancy or insulation under water pressure, although they are less common in circulation.

What Is a Diving Boots?

Diving boots, worn by divers during underwater activities, are also used when walking on land or a ship. There are two main types: one with thick soles, similar to regular shoes, and another with shallow, soft soles resembling socks. The thick-soled type is further divided into the “calendar sole,” featuring a textured surface, and the “deck sole,” which is flat.

Typically, divers wear fins attached to the front of diving boots for underwater exploration. When choosing diving boots, it is crucial to select a pair that fits comfortably on one’s feet and ensures the fins can be worn securely and comfortably. Many thick-soled boots come with fin strap fasteners at the back.

Uses of Diving Boots

Diving boots are employed during diving activities, serving three primary purposes:

Protection from Fins: Diving boots are crucial for safeguarding the feet when fins are worn. Since diving fins are much larger than shoes and exert significant force on the feet during movement, not wearing diving boots can lead to immediate damage, similar to walking barefoot.

Safety for Diver’s Feet: Diving boots protect the soles of a diver’s feet from injuries, especially when walking on decks, sandy beaches, or rocky surfaces. Walking barefoot in such environments poses a risk of foot injuries, which the soles of diving boots help prevent.

Prevention of Body Heat Loss: Thick-material diving boots play a vital role in preventing the drop in body temperature in cold underwater environments. Compared to direct contact of a diver’s toes with water, these boots made of thick material help maintain body temperature by reducing heat loss.

What Is a Diving Glove?

A diving glove is a specialized glove worn by divers in conjunction with wetsuits or drysuits for underwater activities.

Materials like mesh, jersey, and neoprene are commonly used. While some designs feature cut fingertips, the standard design covers all five fingers.

Variations include non-slip grips on the palms, with differing strengths of grip and wristbands that prioritize either water resistance or ease of removal. Divers should consider water temperature and specific activities when choosing their gloves.

Uses of Diving Gloves

Diving gloves protect divers’ hands from hazards such as rocks, coral, and spiky fish. For cold-water diving, gloves with superior insulation and minimal water penetration, usually made of neoprene, are ideal to prevent hand numbness.

In warm-water conditions, non-insulated mesh gloves are popular for their quick-drying properties and hand protection. For underwater photography in warmer waters, gloves with cut fingertips are often preferred.

For activities like spearfishing, gloves with strong non-slip features are beneficial to prevent the spear from slipping.

Principles of Diving Gloves

Underwater, body heat is lost rapidly, leading to the contraction of blood vessels in extremities. Without gloves, divers’ hands and feet may become cold while their body remains warm. Diving gloves are crucial for maintaining body temperature and preventing cold-related adverse effects.

In underwater environments, divers are at risk of being swept by currents and colliding with rocks. Diving gloves offer protection against these hazards.

Types of Diving Gloves

Diving gloves are primarily classified into three types: summer gloves, winter gloves, and 3-season gloves.

1. Summer Gloves

Made of breathable mesh material, these gloves are lightweight and suitable for warm water activities. They allow for precise operations such as handling equipment and dry quickly between uses.

2. Winter Gloves

Designed for colder seasons and water, these are typically made of neoprene, providing high insulation and a snug fit. Their thickness may restrict movement but offers excellent protection against the cold.

3. 3-Season Gloves

Suitable for spring, summer, and autumn, these gloves are often made of jersey material, offering softness, stretch, and breathability.

Other Information on Diving Gloves

Materials of Diving Gloves

Diving glove materials include mesh, jersey, and neoprene.

1. Mesh Material: Offers breathability, lightness, and quick drying, ideal for summer or warm-water dives.

2. Jersey Material: Stretchable and insulating, suitable for spring to autumn.

3. Neoprene Material: Provides insulation against the cold, commonly used in winter or for cold-water dives.

What Is a Sailing Glove?

A sailing glove is a protective glove used by sailing yacht crews, who navigate by harnessing wind with sails.

Yacht steering involves tasks such as untying the halyards (ropes), raising and lowering sails, and changing direction, all requiring frequent rope handling. In environments influenced by waves and wind, sailing gloves are essential for protecting the hands and ensuring precise control in operations.

Sailing gloves come in various types, including styles covering all fingertips, those with cut-off fingertips, and those exposing only the thumb and index fingertips. They are designed to resist tearing when handling moving ropes and are equipped with wristbands to prevent them from slipping off during use.

Uses of Sailing Gloves

Sailing gloves are used for hand protection during yacht steering, which involves extensive rope work such as tying and untying halyards, adjusting sails, and managing rigging. They protect against friction injuries and burns from handling dynamic ropes.

Known for their durability, sailing gloves are also utilized in other marine sports. They offer waterproof and cold-resistant properties, making them suitable for activities like kayaking, canoeing, dinghy sailing, windsurfing, jet skiing, and water skiing.

What Is a Jet Ski Trailer?

A jet ski trailer is a trailer used for transporting jet skis on land.

It is designed with a frame placed on the left and right wheels connected by an axle to carry the jet ski. The frame includes slope rails and a winch for loading and unloading the jet ski, as well as a trailer jack for detaching and securing the trailer from the towing vehicle.

At the front of the trailer, there is a coupler. This coupler is connected to the hitch ball on the rear hitch member of the towing vehicle to enable towing.

The rear of the trailer is equipped with turn signals, brake lamps, tail lamps, and reflectors, similar to those found on automobiles. It also features a license plate.

Uses of Jet Ski Trailer

Jet ski trailers are used to transport jet skis over land to their intended waterfront destinations. Once the jet ski trailer, towed by a vehicle, reaches the destination, the jet ski is launched into the water from the back, pushed by the towing vehicle. With the rear immersed in the water, the slope rails are extended, allowing the jet ski to slide down and be dropped onto the surface of the water.

While the trailer cannot move on its own, it is treated similarly to a motor vehicle on public roads. It requires obtaining license plates appropriate for its size, meeting the lighting requirements for vehicle inspections, and having a total weight exceeding 750 kg when towing a trailer with a jet ski requires a towing license.

What Is a Jet Ski?

Jet ski is one of the names for a type of personal watercraft, a small watercraft that is essentially a water motorcycle. Originally, it was the brand name for personal watercraft manufactured by Kawasaki Motors in the 1970s. Over time, it became a common term used to refer to personal watercraft, replacing the generic term.

Most jet skis use a water jet as a propulsion device, allowing them to travel on water at speeds ranging from 40 to 50 knots. The steering mechanism is similar to that of a land motorcycle, utilizing a handlebar for control. Both steering input and the movement of the rider’s body shift the direction of the watercraft.

There are two main types of jet skis: the stand-up type designed for a single rider and the runabout type with a single-file seat capable of accommodating 1 to 4 people.

Uses of Jet Ski

Jet skis were developed for the purpose of enjoying water-based recreation, making riding them an inherently leisure activity. Other uses include touring for relatively long-distance travel on the water, towing water skiers, and water-based transportation for fishing.

In terms of water sports enjoyment, activities include time trials where riders navigate a set course to compete for the fastest time and races where multiple jet skis compete simultaneously for ranking.

On the practical side, the quick acceleration and high-speed capabilities of jet skis make them useful for water rescue and security operations, utilized by fire departments, police, and similar agencies.

Since a legal amendment in 2003, a special small vessel operating license is required to operate jet skis for example in Japan.